Yes, that's a good point. One idea I have is to set a regular design challenge for an existing open source app. For example, take a particular feature or task f

Yes, that's a good point. One idea I have is to set a regular design challenge for an existing open source app. For example, take a particular feature or task from an open source app and challenge readers to come up with an alternative way of performing that task: How could that feature be implemented in a more user friendly way? I realise there's a danger of being a bit piecemeal in this approach to UX design, but small design challenges like this are still useful and (hopefully) enjoyable to practice.